fix gas limit estimation

Author: Alex Vlasov

Podfile

@@ -4,14 +4,14 @@ def import_pods
   pod 'BigInt', '~> 3.0.1'
   pod 'CryptoSwift'
   pod 'Result', '~> 3.0.0'
-  pod 'libsodium'
-  pod 'secp256k1_ios', :git => 'https://github.com/shamatar/secp256k1_ios.git'
+  pod 'libsodium', :modular_headers => true
+  pod 'secp256k1_ios', :git => 'https://github.com/shamatar/secp256k1_ios.git', :modular_headers => true
 end
 
 target 'web3swift-macOS' do
   platform :osx, '10.13'
   use_frameworks!
-  
+#  use_modular_headers!
   import_pods
 
   target 'web3swift-macOS_Tests' do
@@ -22,7 +22,7 @@ end
 target 'web3swift-iOS' do
   platform :ios, '9.0'
   use_frameworks!
-  
+#  use_modular_headers! 
   import_pods
 
   target 'web3swift-iOS_Tests' do

Podfile.lock

@@ -1,5 +1,5 @@
 PODS:
-  - Alamofire (4.7.1)
+  - Alamofire (4.7.2)
   - Alamofire-Synchronous (4.0.0):
     - Alamofire (~> 4.0)
   - BigInt (3.0.1):
@@ -8,7 +8,7 @@ PODS:
   - libsodium (1.0.12)
   - Result (3.0.0)
   - secp256k1_ios (0.1.3)
-  - SipHash (1.2.0)
+  - SipHash (1.2.1)
 
 DEPENDENCIES:
   - Alamofire (~> 4.7)
@@ -20,7 +20,7 @@ DEPENDENCIES:
   - secp256k1_ios (from `https://github.com/shamatar/secp256k1_ios.git`)
 
 SPEC REPOS:
-  https://github.com/CocoaPods/Specs.git:
+  https://github.com/cocoapods/specs.git:
     - Alamofire
     - Alamofire-Synchronous
     - BigInt
@@ -39,15 +39,15 @@ CHECKOUT OPTIONS:
     :git: https://github.com/shamatar/secp256k1_ios.git
 
 SPEC CHECKSUMS:
-  Alamofire: 68d7d521118d49c615a8d2214d87cdf525599d30
+  Alamofire: e4fa87002c137ba2d8d634d2c51fabcda0d5c223
   Alamofire-Synchronous: eedf1e6e961c3795a63c74990b3f7d9fbfac7e50
   BigInt: 8e8a52161c745cd3ab78e3dc346a9fbee51e6cf6
   CryptoSwift: bca8c5b653dcc2d9734409242a070ff53bafac86
   libsodium: 9a8faa5ef2fa0d2d57bd7f7d79bf8fb7c1a9f0ea
   Result: 1b3e431f37cbcd3ad89c6aa9ab0ae55515fae3b6
   secp256k1_ios: ac9ef04e761f43c58012b28548afa91493761f17
-  SipHash: c6e9e43e9c531b5bc6602545130c26194a6d31ce
+  SipHash: b26918dbe6925368d4322374371437c62c9038e2
 
-PODFILE CHECKSUM: 51415aa233dc66b3af6a71d098467d77a2d23a80
+PODFILE CHECKSUM: e13ad9f4ec7273a5a0d11848b959afdd2efcf396
 
-COCOAPODS: 1.5.0
+COCOAPODS: 1.5.2