add SyncLockMap ctor func

[dogancanbakir]

Proposed changes

SyncLockMap turned out to be very useful as LOC reduction strategy since it can replace any builtin map that requires a mutex. Actually the structure must be initialized with some long boilerplate code as follows:

m := &SyncLockMap[string, string]{
	Map: make(map[string, string]),
}

The task is about implementing a NewSyncLockMap[K,V](...) function that returns new SyncLockMap with the underlying Map initialized. Closes #226.

[Mzack9999]

lgtm!