Removes Boost predicate.hpp dependency

This is a squashed commit that squashes the following commits:

This commit removes the `boost/algorithm/string/predicate.hpp` dependenc
from the project by replacing the function calls to `boost::algorithm::starts_with`
`boost::algorithm::ends_with` and `all` with respectively C++11'
`std::basic_string::front`, `std::basic_string::back`, `std::all_of` function calls

This commit replaces `boost::algorithm::is_digit` with  a locale independent isdigi
function, because the use of the standard library's `isdigit` and `std::isdigit
functions is discoraged in the developer notes

1 files changed, 1 insertions, 3 deletions

diff --git a/src/netbase.cpp b/src/netbase.cpp
index 4ce63cb0ec..607eb89573 100644
--- a/src/netbase.cpp
+++ b/src/netbase.cpp
@@ -20,7 +20,6 @@
 #endif
 
 #include <boost/algorithm/string/case_conv.hpp> // for to_lower()
-#include <boost/algorithm/string/predicate.hpp> // for startswith() and endswith()
 
 #if !defined(MSG_NOSIGNAL)
 #define MSG_NOSIGNAL 0
@@ -121,8 +120,7 @@ bool LookupHost(const char *pszName, std::vector<CNetAddr>& vIP, unsigned int nM
     std::string strHost(pszName);
     if (strHost.empty())
         return false;
-    if (boost::algorithm::starts_with(strHost, "[") && boost::algorithm::ends_with(strHost, "]"))
-    {
+    if (strHost.front() == '[' && strHost.back() == ']') {
         strHost = strHost.substr(1, strHost.size() - 2);
     }