Slight changes to regexp().

Use inline function form and add type annotations. Also add a link to the
README.

Author: Sean1708

README.md

@@ -207,7 +207,7 @@ subtract (generic function with 1 method)
 
 The function that is defined can then be passed to `registerfunc`. `registerfunc` takes three arguments; the database to which the function should be registered, the number of arguments that the function takes and the function itself. The function is registered to the database connection rather than the database itself so must be registered each time the database opens. Your function can not take more than 127 arguments unless it takes a variable number of arguments, if it does take a variable number of arguments then you must pass -1 as the second argument to `registerfunc`.
 
-The `@scalarfunc` macro uses the `sqlreturn` function to return your function's return value to SQLite. By default, `sqlreturn` maps the returned value to a [native SQLite type]() or, failing that, serializes the julia value and stores it as a `BLOB`. To change this behaviour simply define a new method for `sqlreturn` which then calls a previously defined method for `sqlreturn`. Methods which map to native SQLite types are
+The `@scalarfunc` macro uses the `sqlreturn` function to return your function's return value to SQLite. By default, `sqlreturn` maps the returned value to a [native SQLite type](http://sqlite.org/c3ref/result_blob.html) or, failing that, serializes the julia value and stores it as a `BLOB`. To change this behaviour simply define a new method for `sqlreturn` which then calls a previously defined method for `sqlreturn`. Methods which map to native SQLite types are
 
 ```julia
 sqlreturn(context, ::NullType)

src/UDF.jl

@@ -114,11 +114,7 @@ macro scalarfunc(args...)
 end
 
 
-# If ismatch() had a method ismatch(::String, ::String) this could simply be
-# @scalarfunc regexp ismatch
-@scalarfunc function regexp(r, s)
-    r = Regex(r)
-    ismatch(r, s)
-end
-# macro for preserving the backslashes in a string
+# annotate types because the MethodError makes more sense that way
+@scalarfunc regexp(r::String, s::String) = ismatch(Regex(r), s)
+# macro for preserving the special characters in a string
 macro sr_str(s) s end