Adding regex for git version branches

[conniey]

• Builds failing because of missing regex for gitversion.yml.

WARN [01/30/18 16:02:32:20] Could not determine assembly version: GitVersion.GitVersionConfigurationException: Branch configuration 'dev' is missing required configuration 'regex' 
at GitVersion.ConfigurationProvider.ApplyDefaultsTo(Config config) 
at GitVersion.ConfigurationProvider.Provide(String workingDirectory, IFileSystem fileSystem, Boolean applyDefaults, Config overrideConfig) 
at GitVersion.ConfigurationProvider.Provide(GitPreparer gitPreparer, IFileSystem fileSystem, Boolean applyDefaults, Config overrideConfig) 
at GitVersion.ExecuteCore.ExecuteInternal(String targetBranch, String commitId, GitPreparer gitPreparer, IBuildServer buildServer, Config overrideConfig) 
at GitVersion.ExecuteCore.ExecuteGitVersion(String targetUrl, String dynamicRepositoryLocation, Authentication authentication, String targetBranch, Boolean noFetch, String workingDirectory, String commitId, Config overrideConfig, Boolean noCache) 
at GitVersion.ExecuteCore.TryGetVersion(String directory, VersionVariables& versionVariables, Boolean noFetch, Authentication authentication)

[conniey]

Updating build scripts to use /m:1 to avoid periodic issues like:

19:38:07 MSBUILD : warning : WARN [01/30/18 19:36:53:40] Could not determine assembly version: LibGit2Sharp.LockedFileException: The index is locked. This might be due to a concurrent or crashed process [D:\j\w\windows_nt_de---ee233175

GitTools/GitVersion#1031